Mammal Study

We investigated the food habits of Asiatic black bears (Ursus thibetanus) in Oze National Park, Japan, and analyzed the abundance and nutritional content of skunk cabbage (Lysichiton camtschatcense) to evaluate the quality of moorland habitat for foraging bears. Analysis of 141 scats collected from August 2005 to September 2009 revealed that spadices of skunk cabbage were important food items in summer when other foods for bears are scarce. Skunk cabbage is a valuable food resource for Asiatic black bears in terms of nutrition, predictability, quantity, and availability, but it also has several negative features. Moorland that provides high quantities of this food resource appear to be important habitat for Asiatic black bears around Oze National Park. In the conservation and management of Oze National Park, skunk cabbage populations and field signs of bears should be monitored.

The relationship between environmental factors and the occurrence of the Smith's redbacked vole, Eothenomys smithii, was analyzed first by principle component analysis (PCA) to select factors and suitability of fit between capturing results of the voles, and subsequently by multiple regression analysis (MRA) to identify significant environmental factors affecting the occurrence of the vole. Six research sites were established along six valleys showing rocky terrain in the Tenshi Mountains at the foot of Mt. Fuji, Shizuoka Prefecture, Honshu, Japan, where the closely related species, E. andersoni, is absent. Ten environmental factors were examined for the occurrence of the vole in three quadrats at each site. In addition, thirty traps were set at 5-m intervals along the valley (150 m long) for one night at each site, and this trapping was performed four times in one year. As a result of MRA, higher coverage of bryophytes (factor 9) was significantly chosen among the four factors primarily selected by PCA. It is concluded that E. smithii prefers a dense covering of bryophytes in the rocky terrains of small valleys with forests, suggesting conditions of higher moisture and darkness appropriate for bryophyte growth.

The feeding habits of Indian giant flying squirrels (Petaurista philippensis Elliot 1839) were studied in the Sitamata Wildlife Sanctuary, Rajasthan, India, from March 2009 to February 2010. Feeding by flying squirrels was arboreal and consisted entirely of plant materials. Based on 5,071 feeding records, 20 plant species belonging to 13 families were used. Madhuca longifolia was the most eaten species (31.85% of annual diet) followed by Terminalia bellirica (17.11 %), Terminalia tomentosa (9.52%) and Diospyros melanoxylon (8.09%). The most consumed food part was the pith (78.06%) with other plant parts (twigs, leaves, bark, flowers, buds, fruits and seeds) comprising 21.94% of the annual diet. Early night was found to be the most active time for feeding, and feeding reduced until 0530 hrs.

The Japanese marten Martes melampus occurring on Hokkaido Island, Japan, is a domestic alien species, artificially introduced from their native distributional range. To reveal the genetic variation within the Hokkaido marten population and their relationships with native populations, we genotyped 14 individuals from Hokkaido using 10 microsatellite loci, and compared the genotype data with those of native populations reported previously. The Hokkaido population showed the highest number of private alleles and loci with private alleles. Relatively high levels of observed (Ho = 0.514) and expected (He = 0.724) heterozygosities and allelic richness (R = 5.290) suggested that the Hokkaido population maintains polymorphisms in microsatellites. These genetic characteristics in the Hokkaido population could have resulted from random mating in fur farms and/or multiple releases from them. Genetic distances among populations showed that the Hokkaido population is closely related to the Chubu and Kitakyushu populations. Bayesian clustering and assignment tests indicated that the Hokkaido population consists of two genetically distinct lineages. These results suggest that the founders were introduced to Hokkaido from multiple locations in the native distributional range in Japan, and that the descendants still maintain genetic polymorphisms.